People are eager to breathe fresh air in a crowded, stuffy city. Thus, "air freshener" came into being. Most people think that air freshener can purify the air, in fact it does not have this function, it can only cover the stench of the air, and some air freshener will cause a second pollution in the home.

At present, the market sales of "air freshener" summed up only gas, liquid and solid three categories.

Gaseous air freshener has two types: ozone and anion;

Liquid air freshener is mainly made of various spices dissolved in organic solvents;

Solid-state mainly have health incense and incense and other two categories.

Consists of ethanol, essence, deionized water and other components, canned products also contain propane, butane, dimethyl ether and other propellants, and filled with a certain amount of nitrogen and other compressed gas. So that when the use of fragrance to conceal the odor, and can not be caused by the smell of gas such as ammonia, hydrogen sulfide and other reactions, it is impossible to decompose or eliminate such harmful gases.

Therefore, "air freshener" can only confuse people's sense of smell, in certain smelly places, such as toilets, do play a very good role in deodorization, reduce or eliminate the feeling of discomfort, but can not really achieve the role of clean air. Excessive reliance on or excessive use of "air freshener" may pose a health hazard.